Surface condenser



(No Model.)

J RENSHAW SURFACE CONDENSER.

PaJzentqd Sept. 3, 1895.

UNITED STATES JAMES RENSHAW, OF DENVER, COLORADO.

PATENT OFFICE.

SURFACE CIONDENSER.

SPECIFICATION forming part of Letters Patent No. 545,612, datedSeptember 3, 1895.

' Application filed December 28, 189A. Serial No. 533,194- (No model.)

To all whom it mayooncern:

Be it known that 1, JAMES RENSHAW, a citizen of the United States ofAmerica, residing at Denver, in the county of Arapahoe and State ofColorado, have invented certain new and useful Improvements in faurfaceCondensers; and I do declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertai ns to make and use the same, referencebeing had to the accompanying drawings, and to the letters of referencemarked thereon,which form a part of this specification.

My invention relates to improvements in steam-condensers, andparticularly to that class of steam-condensers known as surfacecondensers; and the objects .of my invention are, first, to provide asurface condenser adapted to pumps and pumping-engines; second, toprovide a surface condenser especially adapted to station and sinkingpumps used in deep mining; third, to providea surface condenser in whichthe column of water discharged by the pump acts as the refrigeratingmedium; fourth, to provide a surface condenser which can be attached tothe sta tion and sinking pumps at present in use in mines, and one whichdoes not require addi{ tional space to that occupied by the pump and itssuction and delivery pipes; fifth, to

provide a pump surface condenser in which the water-plungers fulfill thefunctions of an air-pump, and create and maintain a vacuum in thecondenser equal to the vacuum created by the plungers in thesuction-pipe. I attain these objects by the mechanism illustrated anddescribed in the accompanying drawings and specification, in whichFigure 1 represents a sectional elevation of my improved surfacecondenser. Fig. 2 represents a plan View of the same.

Similar letters of reference refer to similar parts throughout both theviews.

Referring to Fig. 1, A designates a pump delivery-pipe, which may beconnected to any make, style, or size of pump. I do not show a pumpconnected to the condenser, but simply show the exhaust-steam pipe B,which connects the steam-chest of the pump to the condenser, and thecondenser dischargingpipe 0, which connects the condenser to thesuction-pipe of the pump. The pipe A represents, in practical usepreferably, one standard length of pipe, which is eighteen feet. It isthreaded at both ends, as is usual, and to each end I thread a flange Dand E. At the lower end a flanged elbow E is represented bolted to theflange E. This elbow leads to and is secured to the discharge-opening ofthe pump. It is used when the discharge-pipe stands in a vertical shaftand the pump has a side delivery; but if the pipe stands horizontal tothe pump, or the pump has a top discharge-opening, this length is bolteddirectly to the pump or a short piece is interposed between them. At theopposite end of the pipe A the adjacent length of pipe G is alsoprovided at its end with a flange G, which is threaded thereto. Throughboth flanges boltholes are drilled to register, and the flange G and thepipe G are bolted to the flange D by the bolts D. One flange is providedwith a counter-bore and the other with a projection fitting therein, butof less depth, leaving a space between the two, in which I place agasket G All the joints of the, condenser are preferably made in asimilar manner. I surround the pipe A with a larger pipe H for thegreater part of its length. I preferably use boilertubing for this outerpipe. It is lighter and less expensive. This pipe H constitutes thecentral portion of the condenser and in a fullfurther secure it byturning the edges of the pipe outward, as shown at K and K. .The

upper end of this pipe and the flange Lbolts to a flange L, which is apart of the condenserhead M. This head is also larger in diameter thanthe pipe A, especially at its central part .N, where I shape it to formquite a chamber around the pipe A. The condenser-head also bolts tothefiange D of the pipe A, the bolts D passing through its top flange L.Adepending circular lip O-is formed on the said flange D, close to thepipe A. It is adapted to fit into the bore of the head and hold itconcentric with the pipe. I provide the head of the condenser with aflanged projecting outlet P, which enables it to be bolted to the flangeB of the exhaust-steam pipe B. The opposite end of the condenser iscomposed of a cylindrical casting Q. This casting is sized condenserwill be about 14 feet long. .On each end I shrink a flange I and J, andI flanged at both ends similar to the head. One end is bolted to thebody of the outer casing or pipe H, and in the other end of the castinga stuffing-box R is formed by counterboring to a desired depth andfitting a flanged gland into the counterbore, which is packed to make atight joint around the pipe. This casting is provided with a flangedprojecting outlet T for the egress of the water which collects as thesteam is condensed. The said outlet is arranged close to the bottom ofthe condensing-chamber T T, the casting being shaped interiorly at thispoint to form an introverted lip T which fits the surface of thedelivery-pipe A and forms the bottom of the condensing-chamber. Theflanged gland U, which fits into the stufingbox R, is adjustably securedto the flange of the casting by the studsR and the nuts V and V. Theflange T of the outlet '1 bolts to the flange X of the suction-pipe C.This pipe leads to the suction-pipe of the pump and can be connected atany convenient part of it, but it is better to connect it just below thepump. I preferably use flanged and bolted joints in the place ofinternal and external threads or couplings, because it is a much better,easier, quicker, and surer way of making and breaking joints in smallspaces.

Before I describe the operation of the condenser I desire to state someof the objectionable features met with in getting rid of or condensingthe exhaust-steam from station and sinking pumps in deep mines. It isobvious that this kind of condenser can be used on all kinds of pumpingplants, and can also be applied to steam-engines if means are employedto keep a stream of cold water flowing through the interior pipe; but ithas been especially designed for the use in gold, silver, copper, andsimilar operative mines, where small and deep shafts are used.Miningshafts vary from four by eight to six by twelve feet square. Thisspace is timbered and is subdivided by timber partitions to form a shaftfor the cage or bucket and a shaft for the pump, and generally aladdershaft for the men. Consequently the space allotted to the stationor sinking pump seldom exceeds but bya few inches, except at the levelsof tunnels, the size of the pump. The live steam is piped in coveredpipes to the pump, which may be several hundred feet below the surface.The exhaust-steam must either be returned to the surface or condensed ator near the pump. It requires expensive piping to carry it again to thesurface, as it must be covered in order to keep the shaft cool, andagain the condensed water from the exhaust causes back-pressure on thepump. Consequently this method is not practical in many cases. Theexhaust-steam must consequently be condensed. There are two ways ofdoing this in common use in the mines. One is to turn the steam directlyinto the sump, which is a hole sunkbelow the station-pump to catch theseepage from the shaft and levels above, and it is at this point confined in a small space that the pump is kept at work to keep the waterbelow the lowest level. This method is objectionable because thesuction-pipe must extend to within a foot or so of the bottom of thesump and the exhaust must be carried below the suction. If this is notdone and the pump gains on the water, the exhaust will eventually bedelivered in the atmosphere of the mine, filling it full of steam, whichmust be avoided. If it is so arranged andthe pump is run at intervals,the exhaust will exhaust against the pressure of a number of feet ofwater, sometimes a good many. This method also keeps the sump-water hotand tends to heat the mine, and owing to the constant agitation of thewater loosens the suction-pipe at its union with the pump. Anothermethod is to run the exhaust-pipe into the suction-pipe. This isobjectionable, for-the reason that the pump will not always catch thewater the first two or more strokes, in which case the exhaust flowsdirectly into the pump-cylinder, heating it upand preventing itscatching the water, as a hot pump will not draw. Again, after the pumpis running the steam enters the suction-pipe in a volume at each strokeand more or less is carried into the cylinder, causing the pump-valvesto keep up a continuous knocking. I have mentioned these methods, asthey are the only ones in use in miningshafts.

There area great many good steam-condensers, but they are not adapted tothe conditions found in underground mining.

The operation of my condenser is as follows: As soon as the pump isstarted up, the exhaust-steam enters the condenser through the pipe Bandsurrounds the delivery-pipe A, filling the condenser-chamber TT. Thischamber being about sixteen feet long, if confined to one length of pipethe steam has quite a distance to travel before it reaches thesuction-pipe of the pump, and as the delivery-pipe A is always cold thesteam is condensed and the water therefrom flows out of the outlet T,through the outlet-pipe G, into the suction-pipe of the pump. Thedeliverypipe averages in the size of mining-pumps in general use fromfour to five times the area of the exhaust-pipe. Consequently in alength of sixteen or more feet avery large area of cold surface isexposed to the steam. Then, again, the cold atmosphere of the mine,together with the constant dripping of seepage-water on the out-sidesurface of the condenser, materially aids in condensing the steam, whichis almost completely condensed before it reaches the end -of thecondensingchamber. When the pump is first started, if it does not catchwater the first few strokes, the pipe A is cold enough to condense thegreater portion of the steam before it reaches the suction-pipe, andassoon as it catches the water a continual stream of cold water isforced constantly through it, thereby keeping IIO it always cold. Thepump-plungers create a vacuum in the condenser equal to the vacuum itcreates in the suction-pipe. The amount of this vacuum in pounds variesaccording to the height of the pump-plungers above the water-level. Thusif the pump is placed eight feet above the water-level the vacuum in thesuction-pipe will be four pounds and the vacuum in the lower part of thecondenser adjacent to T will also be four pounds, and as the steam isalmost entirely condensed this four pounds of vacuum is constantthroughout the condenser to the steam-chest and cylinder and thereforerelieves the steam-piston of that amount of back pressure, therebyincreasing the capacity of the pump or enabling it to do the same workwith less steam, besides ending all annoyance with the exhaust. If thepump is placed twenty feet above the waterlevel, the vacuum in thesuction-pipe and in the condenser will be ten pounds in each.Consequently there will be approximately ten pounds back pressure persquare inch taken from the steam-piston, and as the area of thesteam-piston isgenerally from four to five times that of the plungersevery pound of vacuum takes that amount of back pressure per square inchoff of the piston.

This condenser can be attached to any pump at present in use in themines. It does not require any additional space. It is simple,inexpensive, durable, and makes a perfect condenser.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, is-

1. The combination of one or more lengths of pipe interposed in the pipedelivery of a pump in juxtaposition to its water cylinder,

and provided with pipe connections at each end, a cylindrical castingsurrounding said pipe and secured at one end to one of said pipeconnections, a depending lip on said pipe connection extending into saidcasting adapted to hold it concentric to said pipe, a casing surroundingsaid pipe and secured to said cylindrical casting, a second cylindricalcasting secured to the opposite end of said casing and provided with astuffing box and gland whereby it may be packed around the said innerpipe, an exhaust inlet in the first named casting and a condensed wateroutlet in the second named casting connected respectively to the exhaustand suction pipes of a pump,'as set forth.

2. The combination with one or more lengths of pipe interposed in thedelivery pipe of a pump, provided with a flanged coupling at its end, ofa cylindrical casting surrounding said pipe and secured to saidcoupling, a depending lip on said coupling extending into said casting,whereby it is held'concentric to the pipe, a casing surrounding saidpipe and secured to said cylindrical casting, a second cylindricalcasting secured to the opposite end of said casing, an expansive jointarranged insaid casting around said pipe, an exhaust inlet in the firstnamed casting connecting with the pumps exhaust pipe and an outlet inthe second named casting connected with the suction'pipe of the pump orto an independent air pump, as specified.

In testimony whereof I affix my signature in presence of two witnesses.

JAMES RENSHAW. Witnesses:

EDWARD G. HEOKENDORF, HARRY R. RENsHAW.

